How to POST loop value in PHP?

In the first php page you have a select box

for example

<form name="form1" action="PhpPage2.php">
<select name="dropdown1">
<?php
for($day = 1 ; $day <= 30; $day++){
echo "<option value=".$day.">".$day."</option>";
}
?>
</select>
</form>

Now to get the value of the select box you need to use the following in the second php page (PhpPagae2.php)

<?php
  $dropdown1 = $_POST["dropdown1"];
  echo $dropdown1;
?>

Hope this helps